Conventionally, there has been known an inkjet printing apparatus configured to print images on printing mediums by ejecting ink stored in an ink cartridge through nozzles. Whenever ink stored in an ink cartridge runs out, a new ink cartridge is detachably mounted in such inkjet printing apparatus. For example, Japanese Patent Application Publication No. 2015-196273 discloses an ink cartridge that is attachable to and detachable from a printer.